No area of the business world is more illogically gender imbalanced than law firms. Every year, top law firms recruit 60% female and 40% male law graduates into their practices. Within two years, their female majorities begin to leave. The percentage of female equity partners is now 17% in the top 100 US law firms.

The strangest part is that women lawyers aren’t leaving the profession. They are only leaving law firms, taking on corporate, government or regulatory roles instead.

Law firms who want to hold onto their female recruits can do so – but they need to behave differently. Gianmarco Monsellato, head of TAJ insists it’s only an issue of leadership.

His own firm is 50/ 50 gender balanced, at all levels – including equity partners and governance bodies. It’s fueled their success over the past decade, and TAJ is now the No. 5 law firm in France.

How did he do it? Dramatically differently than most law firms. Most of his competitors have spent years organizing women’s initiatives, networks, or mentoring programs that have done little to increase the percentage of women reaching the top. The National Association of Women Lawyers’ recent report is pretty clear: These “fix the women” approaches have not delivered.

Instead, Monsellato tackled the problem personally. He was involved in every promotion discussion. “For a long time,” he says, “I was the only one allocating cases.” He insisted on gender parity from the beginning. He personally ensured that the best assignments were evenly awarded between men and women. He tracked promotions and compensation to ensure parity. If there was a gap, he asked why. He put his best female lawyers on some of his toughest cases. When clients objected, he personally called them up and asked them to give the lawyer three months to prove herself. In every case, the client was quick to agree and managed to overcome the initial gender bias.

This kind of leadership on gender is rare, but spreading. A growing number of courageous male leaders are working very hard to balance their companies – because they ferociously believe it will enhance their businesses. I spend a lot of time with these kinds of leaders. The smartest among them know that gender balance is more about getting male leaders, and men in general, to push for balance than it is about getting women to change their own behavior.

Monsellato laughs at the ideas of “leaning in” and diversity programs. “If partners aren’t convinced, you won’t get anywhere. And diversity programs headed by women reporting to all-male boards will never work.” He never referred to his gender push as a diversity initiative, and he has never run diversity programs. “What I have done is promote people on performance. If someone works 50% of the time, we adjust that performance to its full-time equivalence. When you adjust performance on an FTE basis, maternity issues stop being an indicator.”

He knows just how hard his female lawyers work, and he doesn’t want to lose out on the benefits of their productivity and ideas. “My biggest issue is trying to stop women from working all the time,” he says, “as technology allows them to work anywhere, anytime.” It’s the “tone from the top” that is key, he insists. Speaking to a roomful of female lawyers at a recent conference, he reminded them, “You are not a minority. It’s about balance, not about gender diversity.”

Interestingly, in my experience, most of the leaders who’ve pushed hardest for gender balance are themselves not fully members of their companies’ dominant majority. They are often a different nationality than most of their colleagues, or the first non-home- country CEO. So, for example, the Peruvian-born Carlos Ghosn at Nissan in Japan, the Dutch Marijn Dekkers at BAYER (disclosure: they are a client) in Germany, or the Italian Monsellato at TAJ in France.

There is nothing better than being a bit of an outsider to understand the particular stickiness of the in-group’s hold on power. These are some of the more enlightened leaders on gender balance. They build true meritocracies, they get the best of 100% of the global talent pool – and they will win a huge competitive edge in this century of globalization.

This blog first appeared on Harvard Business Review on 5/27/2014.

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